• Journal of Power System Engineering
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• v.10 no.2
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• pp.22-28
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• 2006

Computer simulation of the air flow over an automotive vehicle is now becoming a routine process in automotive industry to assess the aerodynamic characteristics of a medium-size vehicle such as $C_d\;and\;C_1$ and aslo to investigate the possibility of improving aerodynamic performance of the vehicle as a preliminary design for the production line. Mainly due to its contribution in saving time and cost in the development of new cars, computer simulation of the air flow over a vehicle is usually done well before a production car is introduced to the market and in gaining more and more attention as powerful computer resources are getting readily available nowadays. To aerodynamically design a car is mainly related with reducing a drag coefficient of car. A well designed car usually has a $C_d$ value in the range of $0.3{\sim}0.4$. It is understandable that automotive industry is rushing to reduce a drag coefficient as reducing even a small fraction of the $C_d$ value can have an enormous overall impact on many areas. Actually, the present research model was able to achieve a $C_d$ value in the range of $0.3{\sim}0.36$ for flow velocities of $60km/h{\sim}100km/h$ by strategically removing the possible factor hazardous to lower $C_d$ value. Prediction of the medium-size vehicle aerodynamics using CFD was performed when an actual car model was in the development stage and three-dimensional modeling was also performed to optimize it as the best model in terms of the best aerodynamic performance.

• Food Science and Biotechnology
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• v.15 no.2
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• pp.202-206
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• 2006

The oxidation stability of fish oil containing omega-3 polyunsaturated fatty acids (PUFAs), which is very susceptible to oxidative deterioration, needs to be improved before it can be successfully applied to functional foods. The antioxidant activities of 17 species of materials in anchovy oil (AO) were compared and a potent antioxidant was determined to improve the shelf-life of refined AO. Antioxidant activities of the 0.05% (w/w) materials in AO were compared against control during storage at $30^{\circ}C$ for 10 days. While no antioxidant effect was shown in alpha tocopherol against control, 3 species of grapefruit seed extracts (GSEs), astaxanthin (AX), soybean lecithin, and green tea extract showed good antioxidant activities. Especially, GSE B, GSE C, and AX showed significantly high peroxide inhibitory activities (PIAs) of $16.2{\pm}2.1$, $20.{\pm}3.5$, and $17.7{\pm}3.5%$, respectively, after the 4th day (p<0.01). Radical scavenging activities (RSAs) of GSE B, GSE C, and AX were $85.1{\pm}0.8$, $95.3{\pm}0.3$, and $85.9{\pm}0.8%$, respectively. Correlation between PIAs and RSAs was high ($R^2=0.926$) in GSE B, GSE C, and AX. Therefore, we concluded that one of the main antioxidative mechanisms of GSEs and AX must operate through an RSA pathway. The $RC_{50}$ (concentration required for 50% reduction of 1,1-diphenyl-2-picryl-hydrazyl, DPPH) of GSE C was $258\;{\mu}g/mL$.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.4
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• pp.2924-2932
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• 2015

This study is for estimate the amount of water supplied data to get a database for economic plan of water supply system by survey for the amount of water supplied of primary, middle and highschool. For this, 54 of primary school, middle school, high school in 6 cities of Kangwon for 5 years. As a result, average of the amount of water supplied per month is $600.7m^3/mon$ and primary, middle schools are $484.2m^3/mon$ and high schools are $833.8m^3/mon$. Average of the amount of water supplied per class is $27.0m^3/mon/class$ and primary, middle schools are $24.4m^3/mon/class$ and high schools are $32m^3/mon/class$. Average of the amount of water supplied per person per day is 55.8l/c/d and primary school, middle schools are 54.4l/c/d and high schools are 58.6l/c/d.

• The Journal of Korean Medicine
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• v.28 no.1 s.69
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• pp.51-62
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• 2007

Objectives . The types of Sasang constitutional medicine (SCM) have definite effect on response to herbal drugs. The majority of human P45O dependent xenobiotic metabolism is carried out by polymorphic enzymes which can cause abolished, altered or enhanced metabolism. Therefore, we evaluated the relation of major CYP2C19, 2D6 polymorphism with Sasang types. Methods : 214 healthy subjects were recruited with informed consent; 172 among them had Sasang diagnosis by QSCC2. CYP2D6, 2C19 polymorphism were determined by PCR-RFLP method. Results : None of the Sasang types showed significant difference in CYP2D6, 2C19 polymorphism. However, the Tae-um type showed relatively low frequency of CYP2D6 $^{*}$10/$^{*}$10 polymorphisms with low activity (p=0.110). In the So-yang type, specific $^{*}$3/$^{*}$3 genotype which is a poor metabolizer of CYP2C19$^{*}$3 was detected (p=0.078).Conclusion . These results suggest that the Tae-um type which is said to have high liver function in SCM has the tendency of high drug-metabolizing enzyme activity. With further study, the CYP polymorphism could serve as a scientific tool for SCM diagnosis.

• Korean journal of applied entomology
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• v.30 no.4
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• pp.258-264
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• 1991

Studies were carried out to investigate effects of temperature and photoperiod on diapause induction and of juvenile hormone III and 20-hydroxyecdysone treatment on diapausing adults of the alder leaf beetle, Agelastica coerulea Baly(Chrγsomelidae: Coleoptera). Its life cycle and ovarian development in adults were also observed. The beetle had one year life cycle with egg, larval, pupal and adult periods being 7-10, 19-21, 14-15 days and about 10 months, r respectively. All adults showed a diapause syndrome when the larvae were reared at $20^{\circ}C$ or $25^{\circ}C$ in combination of photoperiods of 16L/8D, 12L/12D, or 8L/16D. Their ovarioles did not s show any development of vitellogenesis before or during diapause and even when exposed at $15^{\circ}C$ after overwintering. When diapausing adults were treated with JH III they resumed feeding and laid several eggs and broke diapause condition temporally. But diapausing adults treated with 20-hydroxyecdysone did not show any response.

• Journal of Microbiology and Biotechnology
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• v.16 no.10
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• pp.1591-1596
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• 2006

Acaricidal effects of materials derived from Caesalpinia sappan heartwoods against Dermatophagoides farinae and D. pteronyssinus were assessed and compared with those evidenced by commercial benzyl benzoate and DEET. The observed responses varied according to dosage and mite species. The $LD_{50}$ values of the methanol extracts derived from C. sappan heartwoods were 6.13 and $5.44{\mu}g/cm^3$ against D. farinae and D. pteronyssinus, respectively. Furthermore, the ethyl acetate fraction derived from the methanol extract was approximately 8.71 more toxic than DEET against D. farinae, and 4.73 times more toxic against D. pteronyssinus. The biologically active constituent from the ethyl acetate fraction of C. sappan heartwood extract was purified via silica gel chromatography and high-performance liquid chromatography. The structure of the acaricidal component was analyzed by $GC-MS,\;^1H-NMR,\;^{13}C-NMR,\;^1H-^{13}C\;COSY-NMR$, and DEPT-NMR spectroscopy, and identified as juglone (5-hydroxy-l,4-naphthoquinone). Based on the $LD_{50}$ values of juglone and its derivatives, the most toxic compound against D. farinae was juglone ($0.076{\mu}g/cm^3$), followed by benzyl benzoate ($9.143{\mu}g/cm^3$) and 2methyl-l,4-naphthoquinone ($40.0{\mu}g/cm^3$). These results indicate that the acaricidal activity of C. sappan heartwoods is likely to be the result of the effects of juglone. Additionally, juglone treatment was shown to effect a change in the color of the cuticles of house dust mites, from colorless-transparent to dark brownish-black. Accordingly, as a naturally occurring acaricidal agent, C. sappan heartwood-derived juglone should prove to be quite 'useful as a potential control agent, lead compound, and house dust mite indicator.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2011.11a
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• pp.42-42
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• 2011

To evaluate the Hwangsu spring as natural mordants effect on dyeing. The natural mordants effect of Hwangsu spring were analyzed by pH, temperature, trace elements, organic matter and color fastness. Hwangsu spring having pH 2.42 and $14.4^{\circ}C$ was harvested at the end of September, in Yeongcheon (Gyeongbuk Province, Korea) and left on a $0^{\circ}C$ and $25^{\circ}C$ before use. Hwangsu spring during storage at $25^{\circ}C$ turned brown by photochemical reaction. The Result of ICP analysis, it contained Fe(414.9 ppm), Al(88.9 ppm), Mn(4.9 ppm) and observed character by water analysis. Dyeing and post-mordant procedure; Cotton(KS K 0905) were dyed with clove powder for 30 min at $70^{\circ}C$. Hwangsu spring, Aluminium Sulfate $14-18H_20(Al_2(SO_4)_3{\cdot}14-18H_2O)$, Iron Sulfate Heptahydrate($FeSO_4{\cdot}7H_2O$) were used by post mordant at the same ratio. The dyed fabrics were treated with 20% each mordant solution at $25^{\circ}C$ for 10min. Comparison with a reproduced chemical mordant, the K/S values of cotton fabrics dyed with Hwangsu sping were increased.

• Journal of the Korean Society of Clothing and Textiles
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• v.47 no.5
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• pp.839-852
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• 2023

This study examined personal protective clothing, specifically the D (M, L, XL) and C (L, XL, 2XL) levels with high sales rates. The goal was to collect essential data for developing Korean personal protective clothing. There were eight and twelve patterns for the D-level and C-level, respectively. While the pattern dimensions were similar, the chest and waist circumferences (relaxed) were larger in the C-level, and the waist (extended), hip, upper arm circumference, and total lengths were larger in the D-level. The D-level wear sensation worked well for average-sized Koreans in their twenties, but the C-level caused discomfort in multiple areas, such as the face, arms, armpits, hips, crotch, thighs, and knee during movement. Consequently, this region required pattern adjustments and resetting for improved comfort. The grading rules were 10 cm in the chest, waist, and hip circumference, regardless of the level, with slight differences in other parts depending on the levels. Thus, manufacturers should establish new grading rules to suit the Korean body shape.

• Korean Journal of Clinical Pharmacy
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• v.33 no.4
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• pp.270-277
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• 2023

Background: As per guidelines for treating dyslipidemia, the recommended low-density lipoprotein cholesterol (LDL-C) level in extremely high-risk patients, including those with coronary artery diseases is <55 mg/dL. Although this recommendation has been adopted in the guidelines for dyslipidemia in various countries, there is limited evidence of its efficacy in reducing cardiovascular diseases (CVDs), especially among East Asian patients. This study aimed to investigate whether an LDL-C value below 55 mg/dL is associated with decreased risk of CVDs. Methods: Seven clinical trials including 50,970 patients that compared intensive lipid-lowering therapy with less therapy or placebo in patients who had >6 months of follow-up, those with a sample size of ≥150 were selected as the final literature for analysis. Risk ratios (RR) using random effects were represented with 95% confidence intervals (CI) for the reliability of the results. Results: An LDL-C level of <55 mg/dL was related to significantly reduced events of major CVDs (RR: 0.88; 95% CI: 0.80-0.98) and myocardial infarction (RR: 0.81; 95% CI: 0.73-0.90) and a reduced risk of ischemic stroke (RR 0.79; 95% CI 0.69-0.89, mean follow-up=2 years). However, an LDL-C level below 55 mg/dL did not reduce the incidence of CVD in intensive therapy in East Asian patients. Conclusions: A goal LDL-C value below 55 mg/dL was identified to be related to a decreased risk of developing CVD. However, the relation to LDL-C below 55 mg/dL with a decreased risk of CVD was not observed in East Asian patients.

• Advances in materials Research
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• v.13 no.3
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• pp.183-194
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• 2024

D3 tools steel and 440C stainless steel (SS) are normally being employed for application such as knife blade and cutting tools. These steels are iron alloys which have high carbon and high chromium content. In this study, lab work focused on the microstructural and corrosion behavior of D3 tools steel and 440C SS after went through heat treatment processes. Heat treatments for both steels were started with normalizing at 1020 ℃, continue with hardening at 1000 ℃followed by oil quenching. Cryogenic treatment was carried out in liquid nitrogen for 24 hours. The addition of cryogenic heat treatment is believed to increase the hardness and corrosion resistance for steels. Both samples were then tempered at two different tempering temperatures, 160 ℃ and 426 ℃. For corrosion test, the samples were immersed in NaCl solution for 30 days to study the corrosion behavior of D3 tool steel and 440C SS after heat treatment. The mechanical properties of these steels have been investigated using Rockwell hardness machine before heat treatment, after heat treatment (before corrosion) and after corrosion test. Microstructure observation of samples was carried out by scanning electron microscopy. The corrosion rate of these steels was calculated after the corrosion test completed. From the results, the highest hardness is observed for D3 tool steel which tempered at 160 ℃(54.1 HRC). In terms of microstructural analysis, primary carbide and pearlite in the as-received samples transform to tempered martensite and cementite after heat treatment process. From this research, for corrosion test, heat treated 440C SS sample tempered with 426 ℃possessed the excellent corrosion resistance with corrosion rate 0.2808 mm/year.